title: Steady-state relationship of calcium-45 between bone and blood: differences in growing dogs, chicks, and rats.
abstract: In young animals that had received multiple doses of calcium-45, a constant ratio of calcium-45 specific activity in blood to that in bone was found in growing dogs and chicks but not in rats. This steady-state relationship of calcium-45 between bone and blood suggests that during growth in dogs and chicks most of the skeletal calcium is in an active state of turnover. In growing rats, after the first 2 weeks of life, the blood/bone ratio of calcium-45 decreases due to a decrease in bone resorption.
mesh_terms: D000367:Age Factors; D000818:Animals; D001846:Bone Development; D001862:Bone Resorption / Q000187:drug effects; D001842:Bone and Bones / Q000378:metabolism*; D002118:Calcium / Q000097:blood / Q000378:metabolism*; D002132:Calcium Radioisotopes; D002645:Chickens; D004285:Dogs; D012968:Etidronic Acid / Q000494:pharmacology; D006706:Homeostasis; D051381:Rats; D013752:Tetracycline / Q000378:metabolism
chemical_list: D002132:Calcium Radioisotopes; D013752:Tetracycline; D012968:Etidronic Acid; D002118:Calcium